Objective To know the basic hygienic condition of the drinking water safety project in the countryside of Ya'an. Methods The water samples were collected in 2008 and were analyzed complying with the standard protocol of drinking water quality test(GB/T 5750-2006),the basic condition of the water supply was investigated in the same time. Results The main water sources of the researched 133 water supply projects were brook and spring,accounted for 64.66%. The central water supply projects with complete water treatment accounted for 36.84% ,the projects with partial water treatment accounted for 56.39% ,the projects without water treatment accounted for 6.77%. In the projects with partial water treatment, 84% of them had no disinfection facilities. In low flow and ample flow period,the eligible rates of water quality were 26.32%(70/266)and 37.98%(98/258)respectively. The bacteriological indexes were the main influencing factors. Conclusion The centralized water supply projects in the countryside in Ya'an have a high eligible rate in the items,but the bacteria contamination is still a main influencing factor in the rural area drinking water safety.